2025/11/24 by Gantumur, Tsogtgerel
#35J05 #Analysis of PDEs (math.AP) #FOS: Mathematics
paper · doi:10.48550/arxiv.2511.18762
We give a short proof that for a bounded domain Ω⊂ℝn and continuous boundary data g∈ C(∂Ω) admitting a continuous finite-energy extension ϕ∈ H1(Ω)∩ C(Ω), the minimizer of the Dirichlet energy E(v) = ∫Ω |∇ v|2 dx, v-ϕ∈ H10(Ω), coincides with the Perron solution hg of the Dirichlet problem Δu = 0 in Ω with boundary data g. The argument stays entirely in H1(Ω) and uses only strong convergence via strict convexity of the Dirichlet energy, Friedrichs' inequality, Weyl's lemma, and Wiener's exhaustion by regular subdomains. No weak convergence, Poisson problems with distributional right hand sides, or general elliptic theory are needed.